Is it true that all Objectivism stopped being created as of Rand's death?

In the preface of Objectivism, the Philosophy of Ayn Rand (1991, henceforth OPAR), its author, Leonard Peikoff, wrote:

Because of my thirty years of study under her, and by her own statement, I am the person next to Ayn Rand who is the most qualified to write this book. Since she did not live to see it, however, she is not responsible for any misstatements of her views it may contain, nor can the book be properly described as "official Objectivist doctrine." "Objectivism" is the name of Ayn Rand's philosophy as presented in the material she herself wrote or endorsed.

We can only speculate about what OPAR would have been like, had Peikoff set aside "Ominous Parallels" and written OPAR while Rand was still alive and could guide and endorse it (as she did "Ominous Parallels"). But it still remains that, as Rand wrote in 1976 about Peikoff's lecture course on "The Philosophy of Objectivism":

Until or unless I write a comprehensive treatise on my philosophy, Dr. Peikoff's course is the only authorized presentation of the entire theoretical structure of Objectivism, i.e., the only one that I know of my own knowledge to be fully accurate.

Peikoff's main changes in his revision of the lectures were to make some of the arguments more precise and the examples more vivid. But he also substantially changed the logical order of the presentation, and he included new integrations as well.

We can only presume that Rand would have approved of most of the changes Peikoff made between the lectures and OPAR. But since I think there are obvious flaws in the book which were also in the lectures (which Rand approved), I'm not sure that it would have made all that much difference had she been able to take part in "birthing" OPAR.

Anyway, no, OPAR is not "official Objectivism." It is "the definitive statement of Ayn Rand's philosophy—as interpreted by her best student and chosen heir." That is about as good as it is going to get.

For anyone else, it must be truly emasculating, to be recognized as an Objectivist philosopher, but for one's work to fall into the no-man's-land of not being Objectivist philosophy—but merely philosophy by an Objectivist philosopher and inspired by or derived from Objectivism.

How peculiar, and how sad. But that is the logical implication of Objectivism as a "Closed System."